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Related papers: Ergodicity of quantum cellular automata

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A key conjecture about the evolution of complex quantum systems towards an ergodic steady state, known as scrambling, is that this process acquires universal features when it is most efficient. We develop a single-parameter scaling theory…

Quantum Physics · Physics 2025-03-05 Tara Kalsi , Alessandro Romito , Henning Schomerus

Unitarity of the global evolution is an extremely stringent condition on finite state models in discrete spacetime. Quantum cellular automata, in particular, are tightly constrained. In previous work we proved a simple No-go Theorem which…

Quantum Physics · Physics 2008-02-03 David A. Meyer

Understanding out-of-equilibrium quantum dynamics is a critical outstanding problem, with key questions regarding characterizing adiabaticity for applications in quantum technologies. We show how the metric-space approach to quantum…

Quantum Physics · Physics 2018-07-11 A. H. Skelt , R. W. Godby , I. D'Amico

A quantum cellular automaton (QCA) is an abstract model consisting of an array of finite-dimensional quantum systems that evolves in discrete time by local unitary operations. Here we propose a simple coarse-graining map, where the spatial…

Quantum Physics · Physics 2021-08-03 Pedro C. S. Costa

In this paper, we study stable ergodicity of the action of groups of diffeomorphisms on smooth manifolds. Such actions are known to exist only on one-dimensional manifolds. The aim of this paper is to introduce a geometric method to…

Dynamical Systems · Mathematics 2025-01-30 Abbas Fakhari , Meysam Nassiri , Hesam Rajabzadeh

Ergotropy, the maximum work extractable from a quantum system, is a central resource in quantum physics. Computing ergotropy is well established when the system state is fully known, but its estimation under partial information remains an…

Quantum computation based on quantum cellular automata (QCA) can greatly reduce the control and precision necessary for experimental implementations of quantum information processing. A QCA system consists of a few species of qubits in…

Quantum Physics · Physics 2009-11-10 Yaakov S. Weinstein , C. Stephen Hellberg

Quantum mechanics is essentially a statistical theory. Classical mechanics, however, is usually not viewed as being inherently statistical. Nevertheless, the latter can also be formulated statistically. Furthermore, a statistical…

Quantum Physics · Physics 2007-05-23 Rocco Duvenhage

Motivated by a model presented by S. Gudder, we study a quantum generalization of Markov chains and discuss the relation between these maps and open quantum random walks, a class of quantum channels described by S. Attal et al. We consider…

Quantum Physics · Physics 2016-08-10 Carlos F. Lardizabal , Rafael R. Souza

We extend the Nonconventional Ergodic Theorem for generic measures by Furstenberg, to several situations of interest arising from quantum dynamical systems. We deal with the diagonal state canonically associated to the product state (i.e.…

Operator Algebras · Mathematics 2013-06-11 Francesco Fidaleo

We consider the dynamics of an arbitrary quantum system coupled to a large arbitrary and fully quantum mechanical environment through a random interaction. We establish analytically and check numerically the typicality of this dynamics, in…

Quantum Physics · Physics 2017-07-26 Grégoire Ithier , Florent Benaych-Georges

The main focus of this article is the study of ergodicity of Interacting Particle Systems (IPS). We present a simple lemma showing that scaling time is equivalent to taking the convex combination of the transition matrix of the IPS with the…

Probability · Mathematics 2024-07-09 Maciej Głuchowski , Georg Menz

Ergodicity, the property that all allowed configurations are explored over time, plays a pivotal role in explaining the equilibrium behavior of classical dynamical systems. Yet, such a property is typically precluded in quantum systems…

Quantum Physics · Physics 2026-01-21 Wenquan Liu , Zouwei Pan , Yue Fu , Wei Cheng , Wen Wei Ho , Xing Rong , Jiangfeng Du

Quantum systems that violate the eigenstate thermalisation hypothesis thereby falling outside the paradigm of conventional statistical mechanics are of both intellectual and practical interest. We show that such a breaking of ergodicity may…

Disordered Systems and Neural Networks · Physics 2020-05-20 Sthitadhi Roy , Achilleas Lazarides

The positive rates conjecture states that a one-dimensional probabilistic cellular automaton (PCA) with strictly positive transition rates must be ergodic. The conjecture has been refuted by G\'acs, whose counterexample is a cellular…

Cellular Automata and Lattice Gases · Physics 2025-07-08 Hugo Marsan , Mathieu Sablik , Ilkka Törmä

In this paper we introduce a new quantum computation model, the linear quantum cellular automaton. Well-formedness is an essential property for any quantum computing device since it enables us to define the probability of a configuration in…

Data Structures and Algorithms · Computer Science 2007-05-23 Christoph Durr , Huong LeThanh , Miklos Santha

We study the ergodicity of non-autonomous discrete dynamical systems with non-uniform expansion. As an application we get that any uniformly expanding finitely generated semigroup action of $C^{1+\alpha}$ local diffeomorphisms of a compact…

Dynamical Systems · Mathematics 2018-11-26 Pablo G. Barrientos , Abbas Fakhari

Cellular automata, CA for short are continuous maps defined on the set of configurations over a finite alphabet A that commutes with the shift. They are characterized by the existence of local function which determine by local behavior the…

Dynamical Systems · Mathematics 2019-04-30 Rezki Chemlal

We show that in systems with highly degenerate energy spectra, such as the 2D transverse-field Ising model (2DTFIM) in the strong-field limit, quantum chaos can emerge in finite systems for arbitrary small perturbations. In this regime, the…

Quantum Physics · Physics 2025-10-09 Mahmoud Abdelshafy , Rubem Mondaini , Marcos Rigol

Equidistant and non-equidistant single pulse "bang-bang" dynamical controls are investigated in the context of mean ergodic theorems. We show the requirements in which the limit of infinite pulse control for both the equidistant and the…

Quantum Physics · Physics 2017-01-12 J. Z. Bernád